Isuzu N 2008 Series Workshop Manual page 240

Step
1. Remove the Meter (10A) fuse that supplies
voltage to the DPD lamp.
2. Turn ON the ignition, with the engine OFF.
3. Measure the voltage from the DPD lamp
6
control circuit in the ECM harness connector
(pin 9 of J14) to a known good ground.
Is the voltage less than the specified value?
1. Turn OFF the ignition.
2. Reinstall the Meter (10A) fuse.
3. Turn ON the ignition, with the engine OFF.
7
4. Connect a 3-amp fused jumper wire between
the ECM harness connector (pin 9 of J14) and
a known good ground.
Is the DPD lamp illuminated?
1. Turn OFF the ignition.
2. Remove the IP cluster.
3. Connect a test lamp between the ignition
voltage feed circuit of the IP cluster harness
8
connector (pin 2 of B105) and a known good
ground.
4. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?
1. Test the control circuit between the ECM (pin
9 of J14) and the IP cluster (pin 35 of B105)
for an open circuit or high resistance.
9
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
1. Inspect for an intermittent and for poor
connections at the harness connector of the
IP cluster (pins 2 and 35 of B105).
10
2. Repair the connection(s) as necessary.
Did you find and correct the condition?
1. Inspect for an intermittent and for a poor
connection at the harness connector of the
ECM (pin 9 of J14).
11
2. Repair the connection(s) as necessary.
Did you find and correct the condition?
Repair the short to ground between the ECM (pin 9
of J14) and the IP cluster (pin 35 of B105).
12
Did you complete the repair?
Repair the short to battery or ignition voltage
between the ECM (pin 9 of J14) and the IP cluster
13
(pin 35 of B105).
Did you complete the repair?
Repair the open circuit or high resistance on the
ignition voltage feed circuit between the Meter
14
(10A) fuse and the IP cluster (pin 2 of B105).
Did you complete the repair?
Action
Engine Control System (4JJ1)
Value(s) Yes
1 volt
Go to Step 7
—
Go to Step 11
—
Go to Step 9
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Go to Step 17
—
Go to Step 17
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Go to Step 17
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Go to Step 17
—
Go to Step 17
—
Go to Step 17
1A-237
No
Go to Step 13
Go to Step 8
Go to Step 14
Go to Step 10
Go to Step 15
Go to Step 16
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